Before we begin, let's correct this notion that Ronda Rousey is single-handedly responsible for the success – and even the very existence of – women's mixed martial arts.
Rousey had yet to win an Olympic medal when Gina Carano appeared first on Showtime, and then later on CBS. Rousey was more than a year away from her first amateur MMA bout when Carano fought Cris "Cyborg" Justino in the first televised card on a premium cable television network to be headlined by women.
It was Carano, she of the pretty face, aw-shucks demeanor and pulverizing right hand who proved that smart, gifted women could have a legitimate place in the mixed martial arts field.
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It is Carano, not Rousey, who deserves to be regarded as the face of women's MMA. But that's OK, because Rousey's stardom isn't limited to either the women's game or to MMA in general.
She's the biggest star in MMA, period, and one of the most recognizable female athletes in the world.
According to UFC president Dana White, Rousey has made more money after her first two UFC fights than Brock Lesnar made in his. Lesnar was a massive professional wrestling star when he made his debut in 2008.
Rousey had no such base when she made her first appearance on a big MMA stage. She became the first American woman to win an Olympic medal in judo, capturing a bronze at the 2008 Games in Beijing. Judo, though, is about as far from being a mainstream sport as it gets, and just a few months after the Games, Rousey was briefly living in her car, pouring drinks at a Los Angeles bar.
A little more than five years later, she's by far the most in-demand athlete in the UFC, and it's not even close.
For the last two years, Rousey has been on Forbes' coveted "30 under 30" list, which highlights the biggest stars under 30 years old in 15 fields of endeavor.
Rousey was on Forbes' 2013 list in the sports field along with the likes of Kevin Durant of the Oklahoma City Thunder, Bryce Harper of the Washington Nationals and Sidney Crosby of the Pittsburgh Penguins.
For the second year in a row, she was also in Maxim's Hot 100, a poll that gives fans the chance to vote for whom they feel are the 100 most beautiful women in the world. Rousey was No. 29 on the list last year, with voting is still going for 2014.
Even though Carano shoved women's MMA out of the shadows in 2007, it wasn't until Rousey debuted in the UFC last year that the women's version of the sport really took off.
On the night that Rousey beat Carmouche in Anaheim, Calif., exactly 365 days ago, Anderson Silva was the UFC's long-standing middleweight champion and Georges St-Pierre was its highly popular welterweight champion.
A year later, Silva is rehabilitating a broken leg, his future uncertain. St-Pierre has taken a sabbatical, is at odds with management and surrendered his title belt, his future perhaps even murkier.
But still, there is Rousey. She's burst upon the scene like no athlete in MMA history and she's rewriting the definition of what it is to be a success in the UFC.
In the last year, she's won two fights, both by arm bar; coached a season on the UFC's reality show, "The Ultimate Fighter," on Fox Sports 1; filmed two movies and has been chosen for lead roles in two upcoming films.
Oh yeah, and she also defends her bantamweight title Saturday at the Mandalay Bay Events Center in the main event of UFC 170. She'll face Sara McMann in the first bout in UFC history pitting Olympic medalists against each other.
This is who Ronda Rousey is, and it's why she's the most important fighter in the sport right now, male or female.
She not only draws MMA fans, but she cuts across the spectrum of fan bases, even appealing to non-sports fans.
Rousey defies convention. She's got the striking looks of a model and isn't shy about showing off her looks or her figure. She appeared in a bikini on the cover of one magazine and in the nude on the cover of another.
Yet, she's so single-minded, hard-nosed and flat-out tough that she'll compete through just about anything. It takes her a good 20 to 30 seconds to rattle off the list of injuries she's had. Overcome with a horrible case of the flu, Rousey simply kept pushing and trained as if she were feeling perfectly.
She's risen faster and accomplished more in a short time than any UFC fighter in the promotion's 20 years.
"I get asked why she is so popular, and it's hard to say other than just that she has the 'it' factor," White said. "Whatever reason you might come up with, her looks, her sense of humor, her athletic ability, her toughness, whatever, it's all of those things. Whatever it is, people gravitate to her."
Rousey clearly knows how to seize the moment. Take, for instance, the end of her rivalry with Miesha Tate in the co-main event of UFC 168 in December.
Their rivalry was born in 2012, when Strikeforce tapped Rousey, 4-0 at the time, as the challenger for Tate's championship belt. Tate didn't feel Rousey had earned the title shot and felt it should have gone to Sarah Kaufman instead.
That began a rivalry that was as one-sided as it can get. Rousey submitted Tate in that March 3, 2012, match, dislocating Tate's elbow along the way. Last summer, Rousey filmed "The Ultimate Fighter" alongside Tate, spending most of the six weeks engaged in a war of words with Tate.
Rousey then won the second bout so decisively, there would be no more rivalry.
After submitting to an arm bar again, Tate dragged herself slowly off the canvas following the one-sided defeat at UFC 168. Tate had been tossed around like a rag doll, bloodied and convincingly beaten.
For a brief second that seemed like an hour, Tate and Rousey stood face to face, Tate vanquished and Rousey about to head for bigger things. Tentatively, Tate raised her right hand and extended it toward Rousey, offering it in congratulations.
Rousey looked at Tate, sneered, refused to shake hands and stomped to the other side of the cage, where she celebrated her win with her team as the crowd howled in anger.
That move alone probably sold hundreds of tickets and thousands of pay-per-views for the McMann fight. Many loved her brash nature and willingness to thumb her nose at conventional norms. Others were outraged by her lack of sportsmanship.
So, she made loyal fans of that first group, who will come to see what she does next. And she forever angered that second group, which will buy the pay-per-view with the hope that McMann, a 2004 silver medalist in wrestling, will knock Rousey off her high horse.
Rousey says she isn't intentionally playing the bad guy, but is comfortable with the role.
Even before she'd had a legitimately big fight, Rousey had an instinctual feel for how to promote and attract attention.
"I don't consider myself the bad guy, but if people want to see me like that, that's fine," she told Fox Sports Latino in a Feb. 22, 2012 interview. "I want everyone to disagree about me, that's the thing. I don't want everyone to think I suck and I don't want everyone to like me because if there's a general consensus, there's nothing to talk about. I want every single time that my name comes up for it to spark a debate.
"I want everyone to be, 'Oh my God, I love her,' or, 'Oh my God, I can't stand her and I hate her.' That's the kind of thing that if people really disagree, they're really going to want to see that fight."
It's anybody's guess how much longer she fights. She still makes more from fighting than from movies, White said, but that's about to change.
Warner Bros. signed her for two upcoming projects. She'll be a female lead in the "Entourage" movie, which is expected to begin filming next month. And the company also bought the rights to the Brad Thor book, "The Athena Project," specifically as a way to feature Rousey.
She insists she's not letting her movie career get in the way of what is important, but how long that will last is the question. "I'm a fighter, through and through," she says. "It's what I love to do more than anything else."
But being a movie star will eventually bring in far more money than fighting, and movie stars don't have the same risk of injury, or of developing something like chronic traumatic encephalopathy, like so many fighters do.
None of it was planned – after winning her bronze medal, Rousey said she wasn't sure whether she'd give MMA a try – because Rousey is the type who doesn't seek opportunity. Rather, she seizes an opportunity when she sees it.
"If you would have asked me two years ago what I'd be doing right now, I probably would have had no clue," Rousey said. "I'm not good at predicting the future. I don't know where I got this, but I think it's true: Man's plans are proof that God has a sense of humor."
For the time being, though, she's comfortable in the gym and she loves being in the cage. Even just training by herself gives her a sense of peace she can't get anywhere else.
"When I don't have camp, what do I do?" she asked rhetorically. "Two days after I fight, I'm at the gym. It's where I feel like going. It's where I feel I belong. I'm happy there. I'm fortunate that I live and train with Marina Shafir, Jessamyn Duke and Shayna Baszler. They all fight as well, and we all feed off each other's motivation.
"They're seeking the title and I'm still trying to defend it. We all wake up in the morning joking, because it's like we're all on quests to conquer the world. They're so hungry that it keeps me hungry and so I feel like I still have a lot I want to prove in this sport."
White, though, seems to be preparing for the inevitable. Much like his buddy, movie star and ex-pro wrestler Dwayne "The Rock" Johnson, White knows that Rousey may soon outgrow the UFC and become a full-time actress.
But White said rather than rue that day, he'll welcome it. He sees a bit of himself in Rousey, too.
"I've never met anyone who works as hard as Ronda Rousey does," White said. "When I was first putting [the UFC] together, people told me to slow down, that I'd burn out and that I couldn't go that many hours or fly as much as I was flying for very long. Well, here I am. And Ronda is the same way. She called me this morning, and she was so pumped. She said, 'Dana, I just got done with the best workout I ever had.'
"She has been so [expletive] busy in this last year, with everything we've thrown at her and all of the movies and TUF and all of the other [expletive], but she's calling me to tell me she had her best workout ever. Think about that: She hasn't had a minute's break in over a year and she's jacked about this great workout. But that's what makes her so special."